World Resources Institute. A Guide to world resources 2002-2004: Desicions for the earth balance, voice and power. S.n.
Chicago-viite (17. p.)World Resources Institute. A Guide to World Resources 2002-2004: Desicions for the Earth Balance, Voice and Power. Washington, D.C.: S.n.
MLA-viite (9. p.)World Resources Institute. A Guide to World Resources 2002-2004: Desicions for the Earth Balance, Voice and Power. S.n.
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